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Front Suspension
http://www.gtmdrivers.com/forum/front-suspension-t4030.html		 Page 1 of 2
Author:  petesilcock [ Wed May 09, 2018 6:44 pm ]
Post subject:  Front Suspension
https://s14.postimg.cc/rykib5p69/IMG_20 ... 180505.jpg

https://s14.postimg.cc/n16xpjurl/IMG_20 ... 180531.jpg
https://s14.postimg.cc/p5raqmooh/IMG_20 ... 183553.jpg
https://s14.postimg.cc/oszwkh19t/IMG_20 ... 183600.jpg
Author:  petesilcock [ Wed May 09, 2018 6:55 pm ]
Post subject:  Re: Front Suspension
I need to be taught how to do this properly
I can click on the photos and see them but they don't seem to display.

1. I have put a 'bottle screw' into the top link to make the camber (and castor) easily adjustable
Right and Left threads - loosen the lock nuts and turn the centre.

2. Bought roll bar links and shortened to suit - changed from the rose joint rattle units to OEM type
I know rose joints are great for competition but not good for road car

3. Fitted 4lb helper springs - these are coil bound when in use however they stop the springs from escaping from their seats when on full droop
The spring seats were lowered by Dave Gallop to get the underside of the car very slightly lower at the front.
Before adjustment the flat floor was lifting the car with 15mm rake the wrong way.

4. MGF quick rack fitted and new joints where worn.

Pete
Author:  sanzomat [ Wed May 09, 2018 8:10 pm ]
Post subject:  Re: Front Suspension
All looks very good. I like the adjustable top wishbone :D . Did you do that yourself?
Presumably enough metal removed so it can be shorter than it was originally to give negative camber.

The thread on the top ball joint doesn't protrude far from the nyloc - I've always worked on the rule of two clear turns left showing - I guess they were designed for a plain nut with a tab washer? Might be worth checking the tightness of those from time to time, especially as the paint below them might creep a bit.

I like the shorter drop links - any impact on movement ratio (and thus stiffness)? I note you aren't on the stiffest anyway!
Author:  Elansprint [ Thu May 10, 2018 8:12 am ]
Post subject:  Re: Front Suspension
Dave i agree about the nylock but the ball joints i bought have a shorter threaded section but they come with a washer with lock tabs to go under the nut to stop it moving not fitted in photo's. i see the large circular washer under the joint is not peened over to lock it in position although these may have been taken before everything was finished
Ian
Author:  petesilcock [ Thu May 10, 2018 4:44 pm ]
Post subject:  Re: Front Suspension
The pics were during works so not finished
Yes I cut the wishbones and fitted the adjusters
Could not face shimming
Not driven since the links altered
Author:  Matty H [ Tue Jul 31, 2018 9:12 pm ]
Post subject:  Re: Front Suspension
Could you give me details of the front suspension parts interested in doing this myself.
Matty
Author:  petesilcock [ Fri Aug 03, 2018 5:52 pm ]
Post subject:  Re: Front Suspension
https://s15.postimg.cc/d1lrvujpn/IMG_1116.jpg

https://s15.postimg.cc/70o2yyzq3/IMG_1115.jpg

https://s15.postimg.cc/rkswxjfi3/IMG_1114.jpg

Long threaded bar and locknuts to keep dimension of the wishbone.
Screws into backboard to further give dimension of the wishbone
Cut off part of the roll bar plate
Cut wishbone in position that can be easily accessed.
12mm left right threaded bar with nuts and locknuts
Offer up and work out the movement needed -cut out this section of wishbone
Weld nuts to wishbone
Dismantle holding framework.
----- Get camber and castor checked properly!!!!
This can adjust both so may be possible to change the self centering
Mine with Ford v6 should be on the road in the next couple of months
Just now the good summer is better outside than in the workshop
Author:  Matty H [ Wed Oct 24, 2018 10:25 pm ]
Post subject:  Re: Front Suspension
Struggling to find the threaded adjuster where did you get them from and have you used stainless.
Matty
Author:  petesilcock [ Thu Nov 01, 2018 5:52 pm ]
Post subject:  Re: Front Suspension
https://www.gsproducts.co.uk/m10-left-r ... ess-steel/

Here is one
Bought 1/2 nuts right and left

Pete
Author:  Jaykart1227 [ Fri Nov 02, 2018 7:50 am ]
Post subject:  Re: Front Suspension
Just a thought chaps....is stainless steel componentry best avoided for safety critical items such as suspension? I’ve always avoided using it for anything like that because I didn’t think it had the tensile strength? Is A 4 grade stainless ok in this respect?
Author:  sanzomat [ Fri Nov 02, 2018 9:46 am ]
Post subject:  Re: Front Suspension
That link doesn't say what tensile rating the stainless is. You can get high tensile stainless, A4-80, that is similar in strength to 8.8 (but nowhere near 10.9's). Most A4 stainless is A4-70 though. The tensile strength of A4-70 is about 7/8's of 8.8's so not exactly weak but worth thinking about it. What is stronger out of the the original tube and the threaded rod? Where are the stress concentrations? I imagine that fatigue generation would be more likely to lead to failure than the tensile strength of any of the components. I would guess that a system with welded nuts and threaded rods would have a number of places where stresses could concentrate compared to a simple tube.

For camber adjustment I'd say a threaded top joint at the end of the wishbone would be stronger but that wouldn't adjust the caster (and would need to be undone to adjust it).
Author:  Jaykart1227 [ Fri Nov 02, 2018 8:01 pm ]
Post subject:  Re: Front Suspension
Makes sense Dave thanks. I’ve always avoided stainless in any sort of suspension scenario to be on the safe side but I don’t suppose it’s completely necessary.

I’ve had a couple of conversations with Dave Gallop about an adjustable front wishbone (also z cars), I’ll speak more to Dave when he sets my car up but an adjustable joint at the outboard end would be easiest but, dependant on what static / dynamic castor measures at, two adjustable joints at the inboard end would provide full adjustment.
Author:  sidewinder [ Sat Nov 03, 2018 11:42 am ]
Post subject:  Re: Front Suspension
I've had stainless bolts for the front wishbone pivots, lower hub pinch bolt and shock mount for years. I use as an everyday road car which IMO needs be more durable than a track car due to the high shock loading from poor roads unlike super smooth tracks! :D

The issue with making parts out of SS is the welding which can sensitise the SS to stress corrosion cracking (esp if used in a harsh environment) and hot cracking (during cooling) due to low melt impurities in the metal.
Both of these can be offset by good quality material (inc the weld filler material) with proper compositions and good welding technique.
Author:  sanzomat [ Sat Nov 03, 2018 10:41 pm ]
Post subject:  Re: Front Suspension
sidewinder wrote:
good welding technique.


I'd better not use stainless then :oops:
Author:  petesilcock [ Tue Nov 06, 2018 5:37 pm ]
Post subject:  Re: Front Suspension
I think the point is being missed

The top wishbone is a thin walled tube - wall thickness less than 1mm of mild steel
Compared to a 12mm bolt the tube will fail.
Cross section area is around double for the threaded bar compared to the wishbone tube
Correct ref. welding - must be Tig by someone who knows what they are doing
The stress on the wishbone is not great unless you clobber a curb at speed
I would suggest after doing that a check would be needed anyway
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